In Alberta everything that happens comes off the same edge
All the province's mountains are stacked against its western side. That range decides where it rains, manufactures a wind that rises forty degrees in an hour and feeds the rivers that opened the badlands where the dinosaurs turn up.
There are provinces and regions that are a mosaic, with mountains here, a valley there and coast beyond. Alberta is not. Alberta has all its mountains stacked against one side, the western one, and from there it descends without interruption for hundreds of kilometres.
That asymmetry is not a map detail: it is the engine of everything else. The range decides where it rains, produces a wind that raises the temperature forty degrees in an hour, feeds the rivers and, through those rivers, has exposed one of the richest dinosaur sites in the world.
01 A range on one side and twelve hundred kilometres of flat
It is worth fixing the shape first. The province covers 661,849 square kilometres, Canada's fourth largest, and stretches 1,200 kilometres north to south. The highest point is Mount Columbia, at 3,747 metres, and the lowest is 152 metres on the Slave river, inside Wood Buffalo National Park.
Between those two numbers lies the whole territory, and it is arranged in strips. In the west, the Rocky Mountains. Then the foothills. In the centre, a band of open aspen parkland. To the south, the prairie, with the badlands in the south-east. And to the north, the boreal forest.
More than half of Albertans live in one of the two big cities, Edmonton, the capital, and Calgary, the largest, both in the southern half. The rest of the territory is very empty, and that too is a consequence of the edge.
02 The edge distributes the water
The range's first function is intercepting the moisture coming from the Pacific. The province's precipitation figures make it clear: between 300 and 450 millimetres a year across most of the territory, and up to 600 in the mountain foothills.
Three hundred millimetres is a semi-arid figure. The Alberta plain is dry because the mountains take the water first, and the province's south, in the steppe region known as Palliser's Triangle, is the driest part of all.
What does not fall as rain on the flat stays up there as ice and snow, and comes down later through the rivers. It is a deferred distribution system: the mountains store in winter and release for the rest of the year.
03 And it distributes the wind too
The second function is more spectacular. Pacific air crossing the Rockies loses its moisture as it rises and, coming down the eastern flank, compresses and warms. The result is the chinook, a warm, dry wind that sweeps the province's south in the depths of winter.
The figures are hard to believe. At Pincher Creek, some 200 kilometres south of Calgary, on 10 January 1962 the temperature rose from −19 to 22 degrees in a single hour: 41 degrees of difference, the largest one-day change recorded in Canada.
The effect is not anecdotal: it defines the liveability of southern Alberta. Calgary records some 25 chinook days per meteorological winter, that is, one day in three or four between December and February, and that is why its winter is unlike that of the rest of the Canadian prairies.
04 The rivers that cut the plain
The rivers come off the edge too, and they are big. The Athabasca is the province's longest at 1,538 kilometres, and the Peace is the largest by flow. Both rise in the mountains and cross the plain towards the north-east.
But the river that has changed the visible landscape most is neither of those two: it is the Red Deer, in the south. For some 300 kilometres it is flanked by badlands, a relief of gullies and ravines cut into a plain that is otherwise flat.
That cut has a date. The badlands were opened by the rapid downcutting of meltwater when the Laurentide ice sheet retreated, some 13,000 years ago. The plain was slashed open, and what was exposed was the soft rock underneath.
05 And what the plain had stored
That soft rock is Late Cretaceous, and it contains bone. Alberta holds one of the greatest diversities and abundances of Late Cretaceous dinosaur fossils in the world, and at least 38 type specimens were collected within the province.
The most productive site is Dinosaur Provincial Park, in the Red Deer valley, declared a World Heritage Site in 1979. It is not an isolated case: the province has six inscribed sites, and five of the six are a direct consequence of this geography.
The list sums it up: the Canadian Rocky Mountain Parks, Dinosaur Provincial Park, Head-Smashed-In Buffalo Jump, the Waterton-Glacier International Peace Park, Wood Buffalo National Park and Writing-on-Stone Provincial Park. Mountain, badlands, prairie and boreal forest, one per strip.
06 How to travel it
The first practical consequence is that it pays to travel from west to east rather than the other way round. Starting in the mountains and heading out onto the plain is travelling the system in the order in which it works: first the water's source, then the rivers' cut and finally what the cut brought into view.
The second is that the plain is not boring, it is discreet. The badlands are invisible from the road: the plain stays flat right up to the valley rim and only then opens. It is a landscape you have to go and find.
And the third is the one that reorders the trip. If you accept that the Rockies are not the destination but the cause — the one that distributes the water, manufactures the chinook and feeds the rivers that opened the badlands — then Alberta's two halves stop being two different trips and become the beginning and the end of the same one.
